1. Field of the Invention
The present invention relates to ink ejecting heads incorporated in, for example, inkjet printers, and also relates to methods for making the ink ejecting heads. In particular, the present invention relates to an ink ejecting head having no opening on a nozzle sheet for bonding to a head chip and no constraints on the height of a liquid chamber, and also relates to a method for making the ink ejecting head for appropriate bonding of the head chip without raising the production costs.
2. Description of the Related Art
A known ink ejecting head for inkjet printers requires an electrical connection between a head chip having an energy generator for applying energy to ink for ejecting ink droplets, and a printed circuit board controlling the actuation of this head chip.
A known method for establishing the electrical connection therebetween is to connect each terminal of both the head chip and the printed circuit board by wire bonding (see, for example, Japanese Examined Patent application Publications Nos. 6-4325 (in particular, FIGS. 3 and 5) and 6-4329 (in particular, FIG. 7)).
In particular, FIG. 3 of the former document (hereinafter referred to as “Patent Document 1”) shows that lead electrodes 12 of a discharge element 7 (corresponding to the head chip) and electrodes 15 of a substrate 14 (corresponding to the printed circuit board) are bonded together by wire bonding.
In the known method described above, however, the structure of the ink ejecting head requires that wire bonding between the head chip and the printed circuit board be performed on the surface from which ink droplets are ejected (in FIG. 3 of Patent Document 1, on the surface having orifices 9 from which ink is ejected).
To perform wire bonding, openings must be formed on a member having nozzles (orifices) and must be sealed with, for example, resin (in FIG. 3 of Patent Document 1, openings are sealed with sealing agent 17) on completion of the wire bonding. This involves many production processes and thus an increase in production costs.
Moreover, as shown in FIG. 3 of Patent Document 1, the sealing agents are projected from the ink ejecting surface for ensuring insulation and mechanical strength.
The projections may cause feeding problems (such as jamming) of a printing medium or may scratch the printing medium, since the printing medium such as paper slides over the ink ejecting surface. Therefore, the openings to be sealed must be away from the path where the printing medium slides over.